K. M. Yeon

Heterotopic pancreas of the stomach: CT findings correlated with pathologic findings in six patients

AbstractBackground: The purpose of this study was to characterize the computed tomographic (CT) findings of heterotopic pancreas of the stomach. Methods: CT scans of six surgically proven cases of heterotopic pancreas of the stomach were reviewed. Three were dynamic spiral CT scans, with both arterial dominant and late phase scans. In other three, both unenhanced and contrast-enhanced scans were obtained by using conventional techniques. Particular attention was given to the enhancement of the heterotopic pancreas. Pathologic and surgical findings were correlated with CT findings. Results: The locations were in the gastric antrum in five cases and in the mid-body in one. Size ranged from 1 cm to 3 cm (mean = 2.1 cm). Three cases showed homogeneous, strong enhancement similar to the pancreas and consisted mainly of pancreatic acini with the same histologic features as the normal pancreas. Two cases showed poor enhancement and consisted mainly of ducts and hypertrophied muscle; pancreatic acini were a minor component. In one case appearing as a cystic lesion on CT, a pseudocyst was found with many ducts and some nests of pancreatic acini. Conclusions: Heterotopic pancreas of the stomach showed a diverse spectrum of CT findings. Good understanding of these CT findings may be helpful in making a correct diagnosis.

Undifferentiated embryonal sarcoma of the liver: US and CT findings

Six cases of undifferentiated embryonal sarcoma (UES) were reviewed to determine their characteristic features on ultrasonography (US) (n=5) and computed tomography (CT) (n=6). US demonstrated a single large, echogenic mass with some anechoic spaces. Contrast-enhanced CT scan revealed a well-demarcated low-attenuation mass with hyperdense septations of variable shape and thickness. Discrepancy of internal architecture on US and CT was one of the important characteristics of UES. CT numbers were 25–47 HU in low-attenuation areas. Enhancing peripheral rim was found in four cases and some solid portions at the periphery or adjacent to the septa were found in all cases. Two patients who had follow-up US and CT without treatment showed enhancing solid portions, changing to hypodense as the tumor grew. When compared with the pathologic findings, US showed a more accurate representation of internal architecture than did CT. Familiarity with these US and CT findings of UES of the liver will be helpful in the differential diagnosis of primary hepatic tumors in childhood.

Complex bronchopulmonary foregut malformation: extralobar pulmonary sequestration associated with a duplication cyst of mixed bronchogenic and oesophageal type.

Abstract We report a 13-year-old girl with an unusual, complex bronchopulmonary foregut malformation. The malformation included extralobar pulmonary sequestration and a duplication cyst of mixed bronchogenic and oesophageal type. Preoperative CT and MRI demonstrated the cystic and solid portions of the mass and indicated an aberrant vascular supply, suggesting the possibility of bronchopulmonary foregut malformation and several other differential diagnoses. A direct communication between the cyst and the bronchus of the sequestrated lung was found on pathological examination. This unusual combination of an extralobar pulmonary sequestration and a foregut cyst points to a common embryological pathogenesis.

Hepatic Hemangioma: Contrast-Enhancement Pattern during the Arterial and Portal Venous Phases of Spiral CT

The objective of the present study was to evaluate contrast-enhancement patterns of hepatic hemangioma according to size during hepatic arterial (30-s delay) and portal venous (65-s delay) phases of spiral computed tomography (CT). During a 10-month-period, 73 patients with 118 hemangiomas underwent two-phase spiral CT examination. The enhancement patterns of tumors were divided into four types based on the attenuation of surrounding liver parenchyma: peripherally nodular high, uniform high, iso, and low. The diameter of the tumors were <10 mm (n= 39), 11–20 mm (n= 33), and >21 mm (n= 46). Overall, the most common enhancement patterns of hemangioma were peripherally nodular high (66/118, 55.9%) during the arterial and portal venous phases. The second most common contrast-enhancement patterns of hemangioma were uniform high (15/118, 12.7%) during the arterial and portal venous phases. In tumors smaller than 20 mm, 11 (9.3%) had low-low attenuation and two (1.7%) had iso-low attenuation during the arterial and portal venous phases, respectively. In conclusion, at two-phase spiral CT, the most common contrast-enhancement patterns of hemangioma are peripherally nodular high and/or uniform high during the arterial and portal venous phases. However, hemangiomas smaller than 2 cm may have atypical enhancing patterns including low and iso-attenuation.

Hemolytic uremic syndrome: MR findings of CNS complications.

MR findings of a patient with hemolytic uremic syndrome involving the CNS are described. Abnormal high signal intensity on T2-weighted images combined with swelling in the lentiform nucleus, posterior limb of internal capsule, external capsule bilaterally, and left extreme capsule was shown on initial MR; a small low signal intensity in the left putamen on T1-and T2-weighted images and generalized atrophy in the area of high signal intensity on previous T2-weighted images was shown on follow-up MR. These findings indicate infarct with focal hemorrhage, which is one of the histopathological features of CNS complication in hemolytic uremic syndrome.

Cystic intrapulmonary lymphangioma: HRCT findings

We report a rare case of cystic intrapulmonary lymphangioma involving the left lung, which presented with pneumothorax and respiratory distress in a 6-month-old infant. Chest radiographs showed a multicystic lesion in the left lung mimicking the features of congenital cystic adenomatoid malformation of the lung. The lesion appeared on high-resolution CT (HRCT) as a multiseptate, air-filled cystic lesion in the left hilar area. Associated HRCT findings were thickening of interlobular septa and bronchovascular bundles in the left lung and the presence of peripheral pulmonary vessels within cystic lesions in the apex of the left lung. HRCT findings correlated well with histopathologic findings. We suggest that these associated findings may be helpful in distinguishing this condition from other cystic lung diseases and that this entity should be included in the differential diagnosis of multicystic lung lesions.

Undifferentiated embryonal sarcoma of the liver treated with chemotherapy : CT imaging in four patients

Background:The purpose of this study was to describe the computed tomography (CT) findings of undifferentiated embryonal sarcoma after chemotherapy and to correlate the CT imaging findings with pathologic findings.Methods:Ten CT images obtained before and after chemotherapy in four patients with hepatic undifferentiated embryonal sarcoma were retrospectively reviewed and correlated with pathologic findings.Results:After chemotherapy, tumor volume decreased by 50–90% and initially nonresectable tumor or gross residual tumor was successfully excised in three patients. In all patients, enhancing peripheral solid portions and septations changed to low-attenuation areas, and in three patients increased or de novo calcifications were found at the periphery of the tumor. Resected pathologic specimen after chemotherapy showed well-encapsulated masses with central necrosis, fibrosis, and dystrophic calcifications.Conclusions:These CT findings will be useful in monitoring the treatment response of hepatic undifferentiated embryonal sarcoma during chemotherapy.

Inflammatory pseudotumor of the lung manifesting as a posterior mediastinal mass

A case of inflammatory pseudotumor of the lung in a 6-year-old boy is presented. The respiratory illness presented as a mycoplasma pneumonia and there had been a similar episode of mycoplasma pneumonia one and a half years previously. Computed tomography revealed a large, calcified right posterior mediastinal mass and exploratory thoracotomy revealed a large posterior mediastinal mass that had an endobronchial component and grew exophytically from the lung. The present case suggests that inflammatory pseudotumor of the lung can manifest as a mediastinal mass and could be associated with mycoplasma pneumonia infection.

Radiological evaluation of pulmonary vein obstruction including two examinations by magnetic resonance imaging

AbstractsCongenital obstruction of the pulmonary vein without anomalous drainage can cause long-standing pulmonary congestion and pulmonary arterial hypertension, and it may include stenosis of individual pulmonary veins and pulmonary vein atresia. We reviewed seven cases of pulmonary vein obstruction, five of which were accompanied by other cardiac anomalies. Right pulmonary veins were involved in all seven cases; one case was bilateral. Pulmonary veins were occluded totally in five and partially in three lungs. Diagnostic pulmonary catheterization and angiography were performed. Chest radiographs of total occlusion cases showed decreased lung volume, features of pulmonary edema, interstitial lesions, and pleural changes, which were quite specific, whereas pulmonary venous dilatation was the dominant finding in partial obstruction cases. Pulmonary perfusion scan (n=3) showed total perfusion defects in the cases with total occlusion of pulmonary veins. Magnetic resonance (MR) imaging (n=2) demonstrated totally occluded pulmonary veins at the venoatrial junction in two lungs and membranous focal obstruction in one lung. Two children underwent pneumonectomy and had the diagnosis histologically confirmed. Although catheterization and angiography are essential for the diagnosis of pulmonary vein obstruction, MR imaging is a useful adjunct.

Castleman disease with renal amyloidosis: imaging findings and clinical significance

We report two cases of renal amyloidosis associated with mesenteric and mediastinal Castleman disease of plasma cell type. Computed tomographic (CT) scan revealed a mesenteric mass with multiple nodal enlargement in one patient and a right paratracheal mass with irregular central calcifications in the second patient. Renal ultrasonography (US) showed increased echogenicity of the renal parenchyma with prominent medullas. Doppler waveform obtained in the kidney associated with mesenteric disease showed complete absence of diastolic flow signal, although it was normal in the patient with mediastinal disease. Recognition of Castleman disease as the cause of renal amyloidosis and the understanding of CT and US findings of this entity are important for the management, as well as its diagnosis.